PCT adaptations

• Long tube increases surface area for absorption, it's wall is made of a single-cubodial-cell layer which have microvilli on their luminal membrane also increasing surface area
• Tight junctions between cells ensure movement occurs through cells (pct lumen into blood capillaries) and not laterally between them, also it is surrounded by a capillary network providing short distance for reabsorption
• PCT wall cells have many mitochondria to provide ATP for active transport of glucose, amino acids and sodium ions, also there are many transport proteins in epithelial membranes
• Infoldings of basal membrane gives large surface area for movement of substances into blood, and it's large network of RER synthesises membrane protein carriers and channels
• PCT Diagram

  A) Capillary

  B) microvilli

  C) basal interdigitation

  
• PCT cell

  A) microvilli

  B) luminal membrane

  C) Glucose

  D) Lumen

  E) proximal

  F) Tight junction

  G) Na^+

  H) Rough Endoplasmic Reticulum

  I) mitochondrion

  J) lateral

  K) Glucose channel protein

  L) Basal

  M) Basement

  N) Glucose

  O) Na^+

  P) K^+

  Q) Na^+/K^+ pump

  R) Na^+

  S) Na^+

  T) K^+

  U) Na^+

  V) Glucose

  W) glucose

  X) endothelial

  Y) capillary

  Z) Blood plasma

  [) pore